SPECIFICATIONS Brand Name: NEWBOLER Mounting Placement: Handlebar Power Supply: Battery type: Bike headlight/Bicycle Computer/ cycling horn 3 in 1 feature 1: Bicycle headlight/Cycling Speedometer/Bike Bell 3 in 1 feature 2: Cycling Stopwatch/Bicycle light / Bike speaker 3 in 1 Version: wireless Screen size: 2.1 inch LCD screen LED: 2 T6 LED Lumens: 800LM Battery: 4000 mAh Lithium battery Speaker: 120 db   The Best Way for Installation The best installation position of the magnet is on the top of the bicycle spoke. The top of the bicycle spoke has a non-circular structure. After the magnet is locked, it will not swing back and forth, and the wireless signal is stable.The distance between the magnet and the sensor should be kept at about 6mm. If it is too close, it may become unstable.The magnet corresponds to the center position of the transmitter liked the picture showed, and the signal is more stable and accurate. Features 800 Lumens Bike headlight gives you awesome visibility and keep safe distance in the dark.Bike speedometer with accurate tracking on speed and distance helps you to get more fun of your cycling trip or easily achieve your fitness goals. 120dB speaker provide a clear warning for passers-by riders and cars.Please enjoy cycling with this wonderful gadget in the anytime to feel your speed!   Specifications Name：NEWBOLER Bike Computer Horn LightHeadlight brightness: 800 lumensLighting mode: High/Low/FlashEffective range: 200mElectronic horn: About 120 dB Lamp Light working time: 5hrs/10hrsComputer working time: 3000hrsRechargeable Battery: 4000mAhCharging mode: USB charging Recharge time: 4hrsSensor battery: CR2032Sensor working time: 12months, 1hr/dayWaterproof: IP65Weight: about 145g Size: about 110*40* 35mmColor: Red / Blue / Green / Black Turn on/Turn off/Standby mode Turn on : Long press Power button after 3 seconds , bike light and odometer will turn on at the same time. Turn off: Long press Power button after 3 seconds at any status, bike light and odometer will turn off and the screen does not display.Standby mode: After turn on, the screen will turn into standby mode when there is no any movement after 4 minutes, only clock and battery power will be displayed. Bike computer Bike speedometer with accurate tracking on speed and distance helps you to get more fun of your cycling trip or easily achieve your fitness goals. 12 FUNCTIONS BIKE COMPUTER: top/current/average Speed, distance, lighting, LCD back light, clock, time, calorie, auto turn off/data storage, power saving etc; Connection Bike odometer sensor connect with magnetic by wireless, bike bell connect body by wiring .The working principle of wireless versionwireless distance ≤ 55 cm/21.65 inchdistance between magnet and launcher should be 3 mm or so   Bright back light 2.1’ big screen LCD display with sustained backlight，allows you to read the digital clearly in the deep dark night or in the long tunnel.